Littmann 3M Classic III stethoscope with laser engraving option and carrying case The 3M™ Littmann® Classic III™ stethoscope is the latest version of the stethoscope that is already helping millions of healthcare professionals get the best possible results. It provides high acoustic sensitivity for excellent performance and a flexible two-sided cone with tunable diaphragms. At the same time, the Littmann Classic III stethoscope is used by students and healthcare professionals alike.